Some ways to earn even after death:
1. Give a copy of Al-Quran to someone. Every time they read from it, you gain.
2. Donate a wheelchair to a hospital. Each time a sick person uses it, you gain.
3. Teach someone some valuable knowledge. Whenever they make use of the knowledge, you gain.
4. Participate in building a mosque or a school. For all beneficial activities in the mosque/school, you gain.
5. Place a water cooler in a public place. Every time a person drinks from it, you gain.
6. Plant a tree. Whenever a person or an animal sits in its shade or eats from it, you gain.